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Lucas Bajolet
ec1d2e68f5
Fingerprints are how we link a packer build to an iteration on HCP. These are computed automatically from the Git SHA in the current state, and are unique to the bucket/iteration. The main problem with this approach is that while sound in theory, it quickly falls apart when users want to run the same build configuration twice, but expect a new image to be created. With the current model, this fails, as the iteration with the current SHA already exists. While this is solvable through environment variables, or by committing a change to the repository, we think this is not clear enough, and causes an extra step to what should otherwise be a simple process. Therefore, to lower the barrier of entry into HCP, we change this behaviour with this commit. Now, fingerprints are randomly generated ULIDs instead of a git SHA, and a new one is always generated, unless one is already specified in the environment. This makes continuation of an existing iteration a conscious choice rather than something automatic, and virtually eliminates conflicts such as the ones described above.